I'll definitely be leveling, got it all set up as well. with a group of friends.
I can do Archaeology in between the queues of heroics at level 85 and such, my main professions (Alch & Herb) should scale up as I level as well (gathering herbs while I quest).
Starting off in Hyjal with the quests while constantly running dungeons with my friends as well. It's not the fastest way, but the best way to gear up and learn the new combat style of using a lot of CC and taking different approaches to fights for level 85 heroic and raiding content. The combat style was more or less the same in classic, which I also played, and I'm glad it's coming back. Now it'll actually make dungeons and heroics more of a challenge rather than a 10 - 15 minute faceroll.